污水处理系统双氯芬酸的迁移转化特征及净化机制

Diclofenac (DCF) which is an emerging pollutant had raised worldwide concern from scientists and the public due to its frequently detection and potential toxic effects. Wastewater treatment plants (WWTPs) is a significant source of DCF into aquatic environment. Clarifying the distribution and transfer of DCF is the precondition to remove it from WWTP, and developing the advanced reduction technologies is important to keep the ecological safety. This research intends to study the existence, distribution of DCF and its metabolites in typical WWTPs. Besides, the transportation and transformation behavior of DCF in WWTPs under different environmental factors will be systemic investigated. Furthermore, the catabolic pathway and regulation for biodegradation of DCF will be explained, as well as the effects of DCF on microbial function and effluent of WWTPs will be identified. Finally, the advanced treatment processes of DCF from the effluent performance of WWTP will be discussed, and the ecotoxicology of DCF on aquatic organism will be also identified. This study contributes not only to the removal of DCF, but also to the ecosystem safety of aquatic environment.

双氯芬酸(Diclofenac，DCF)是近年来水环境中高频检出的具有高生态风险的“新兴”污染物，污水处理系统是其进入环境的重要途径。阐明污水处理系统DCF的分布特征及其迁移转化规律是控制其污染的前提，进而研发安全经济高效的深度净化技术是保障水环境生态安全的重要手段。本项目采用现场调查和室内研究相结合，系统研究DCF在典型污水处理系统的赋存形态和分布特征；揭示DCF在污水处理系统的迁移转化规律及关键影响因子，获得有效去除DCF的污水处理工艺及其条件，阐释污泥中降解DCF的关键微生物及代谢途径；探讨环境浓度DCF长期选择性压力对污水生物处理效能和出水水质的影响机制；揭示污水处理厂二级生化尾水中DCF的深度净化机制，通过对污水生化处理和深度处理DCF净化效果的技术经济分析比较，研发安全经济高效的DCF净化方法。研究结果为水环境DCF污染控制原理和技术创新研究提供科学依据。

本项目选择5种典型污水处理工艺（氧化沟工艺、AAO工艺、AO工艺、倒置AAO-MBR工艺、SBR-BAF工艺），采用现场调查和室内研究相结合，系统研究了常见非甾体抗炎药（NSAIDs）—双氯芬酸（DCF）、布洛芬（IBP）和萘普生（NPX）沿污水处理系统全流程的赋存形态和季节变化特征；揭示了NSAIDs在污水处理系统的迁移转化规律、关键影响因子及其生态风险；深入阐释了污水生物处理系统功能微生物（硝化细菌和异养细菌）对NSAIDs的去除动力学及其代谢机制；阐明了环境浓度DCF长期选择性压力对污水生物处理效能和出水水质的影响机制；探索了污水生化处理系统DCF的强化去除工艺条件；阐述了污水处理厂二级生化尾水DCF的深度净化机制，研发了生物强化净化、高级氧化耦合BAC强化净化DCF的技术方法；揭示了DCF及其高级氧化产物对发光细菌和水生生物（鲫鱼）的生态毒性效应及其作用机制。研究结果为水环境DCF污染控制原理和技术创新研究提供科学依据。